Compressed-gas circuit interrupter



July 8, 1969 R. G. COLCLASER, JR., ET AL 3,454,734

COMPRESSED-GAS CIRCUIT INTERRUPTER Shet Filed Sept. 22, 1965 er, Jr..0nd

x o y w? m m Em k m m l Y C v. H M mm 23 I 0 OINS 3 mm ATTORNEYCOMPRESSED-GAS C IRCUIT INTERRUPTER Sheet Filed Sept. 22, 1965 HIGHPRESSURE 2 G F .m 3 3 3 "w 0 T 4 3 5 fl m A q a 4 m H 5 v Q 7 j x H N Mx/ 5 I 3 4 1 3 W N U l W 6 l R P July 8, 1969 R. s. COLCLASER, JR. ET ALCOMPRESSED- (ms CIRCUIT INTERRUPTER Sheet 1 Filed Sept. 22, 1965 FIG. 3.

m o 3 a w u C 5 3a 5 34 5 m A. 5 u 3 3 42 w u w A an 3 ||||M\ V y 2 a 5w w m y 5 vvvlll m f m :vm w llll cocoa O 4 7 3 4 I 2 h w I 1 3 4 /.W. W5 5 4 N w u United States Patent Otfice COMPRESSED-GAS CIRCUITINTERRUPTER Robert G. Colclaser, Jr., Franklin Township, Delmont,

and Russell N. Yeckley, Murrysville, Pa., assignors to WestinghouseElectric Corporation, Pittsburgh, Pa., a

corporation of Pennsylvania Filed Sept. 22, 1965, Ser. No. 489,228 Int.Cl. H01h'33/82 US. Cl. 200-148 11 Claims ABSTRACT OF THE DISCLOSURE Thisinvention relates, generally, to compressed-gas circuit interr'uptersand, more particularly, to compressed-gas circuit interrupters havinginterrupting units enclosed within pressurized tanks.

A general object of the present invention is to provide an improvedcompressed-gas circuit interrupter of the presurized-tank type, which ishighly effective, may be utilized in multiple modular form, and, inaddition, uses a downstream blast-valve construction.

A more specific object of the present invention is to provide animproved pressurized-tank type of compressed-gas circuit interrupter inwhich a movable tubular contact moves along an exhaust passageway, theflow of gas through which is controlled by a downstream blast valve.

Still a further object of the present invention is to provide animproved pressurized-tank type of high-voltage compressed-gas circuitinterrupter in which a tank means is supported up in the air by aninsulating column, the tank means containing a pressurized gas, and oneor more serially-related arc-extinguishing units are disposed interiorlyof the tank means, each unit containing a movable tubular contactmovable along an exhaust passageway, and pneumatically connected with adown stream blast valve.

Prior circuit breakers for extra-high-voltage service are of the livetank type where the insulation to ground is supplied by a porcelainsupporting column instead of by a gaseous medium. Also in prior- SFbreakers of the dual-pressure type, the SF 'gaS is stored in ahigh-pressure chamber and admitted through an upstream blast valve intoan interrupting unit, or units disposed within a low-pressure chamber.

Another object of this invention is to provide a circuit breaker whichmay include one interrupting unit, or two or more units connected inseries, each unit being enclosed within a metal pressurized tank, whichis supported and insulated from ground by a supporting column composedof porcelain or other insulating material.

Another object of the invention is to provide a circuit breaker of thedual-pressure type in which each interrupting unit is enclosed in a tankcontaining an interrupting gas at a relatively high pressure, and whichis exhausted through a downstream blast valve into a lowpressure chamberduring an interrupting operation.

steel tank 14,

Patented July 8, 1969 A further object of the invention is to provide adouble-break interrupter having two relatively stationary contactmembers and two series connected tubular movable contact members havingan exhausting flow of gas therethrough.

Still another object of the invention is to provide a double-breakinterrupter having two series connected movable tubular contact memberswhich are moved in opposite directions during an interrupting operation.

A still further object of the invention is to utilize one downstreamblast valve to cause an interrupting gas to flow through twoseries-connected hollow moving contact members of an interrupter.

Other objects of the invention will be explained fully hereinafter, orwill be apparent to those skilled in the art.

In accordance with one embodiment of the invention, the contact assemblyof a double-break interrupter is enclosed in a steel tank containingsulfur hexafiuoride, (SF gas at a relatively high pressure. The tank issupported and insulated from ground by an upstanding insulating columncontaining SF gas at a relatively low pressure. A spring-biaseddownstream blast valve normally closes the entrance to the upstandingcolumn. During an interrupting operation, gas flows downwardly from thepressurized tank through two series-connected, hollow, rotatable contactmembers and a downstream blast valve into the upstanding supportingcolumn, thereby interrupting the arcs drawn between the moving contactmembers and the stationary contact members.

For a better understanding of the nature and objects of the invention,reference may be had to the following detailed description, taken inconjunction with the accompanying drawings, in which:

FIGURE 1 is a diagrammatic view of a circuit-breaker structure embodyingprincipal features of the invention.

FIG. 2 is a view, partly in elevation, and partly in section, of onepole units of the breaker shown in FIG. 1, the contacts being shown inthe closed-circuit position;

FIG. 3 is a fragmentary View, somewhat similar to that of FIG. 2, butillustrating the position of the movable contact members during anopening operation; and,

FIG. 4 is a diagrammatic view of the hydraulic actuating mechanism foreflFecting opening of the contact structure.

Referring to the drawings, and more particularly to FIG. 1 thereof, thecircuit-breaker structure 10 shown therein includes two interruptingassemblies 11 and 12 which are connected in series-circuit relationthrough a conductor 13. The interrupting assemblies 11 and 12 constituteone pole-unit 10. As many pole units 10 as desired may be provided.Thus, in a three-phase power system, three pole-units 10, similar to theone illustrated, would be required. Furthermore, one or a plurality ofinterrupting assemblies 11, 12 may be provided for each pole-unit 10depending upon the voltage of the power system.

The interrupting assembly 11 comprises a pressurized which is supportedand insulated from ground by an upstanding porcelain column 15 mountedupon a base housing 16. As indicated in FIG. 2, the base housing 16contains a high-pressure tank 18, a compressor unit 19, and a hydraulicmechanism compartment 20.

A terminal bushing 21 is mounted upon an angularlyextending collar 22 onthe pressurized tank 14. A similar bushing 23 is mounted upon ahorizontally-extending collar 24 on the tank 14. The interruptingassembly 12 is similar to the assembly 11 except that the bushings 21aand 23a and the collars 22a and 24a extend in different directions onthe tank 14a from the directions of the corresponding members on thetank 14.

As indicated in FIG. 2, the pressurized tank 14 contains an interruptinggas, such as sulfur hexafiuoride (SP gas, at a relatively high pressure,for example, 200 p.s.i.g. The supporting column 15 contains sulfurhexafluoride (SP gas at a relatively low pressure such as 30 p.s.i.g. Anopening 25 between the tank 14 and the column 15 is normally closed by adownstream blast valve 26, which is biased to the closed positionagainst a valve seat 27 by a compression spring 28. Low-pressure SP gasis drawn from the column 15, compressed by the compressor 19 andsupplied to the interior of the tank 14 through an insulating tube 29disposed inside the supporting column 15. The bushings 21 and 23 may begas-filled, oil-filled, or shellac-impregnated, as desired.

The current path through the interrupting assembly 11 extends from thebushing 21 through relatively stationary contact fingers 31 mounted in acontact foot 32 on the inner end of the terminal bushing 21, a hollowmovable contact member 33, which is engaged by the fingers 31, and iscarried by a rotatable arm 34, a springbiased contact member 35, whichbridges the arm 34, and a similar arm 340, a hollow contact member 33acarried by the arm 34a, contact fingers 31a and a contact foot 32asecured to the terminal bushing 23. Thus, the movable tubular contactmembers 33 and 33a are connected in series-circuit relation, and theassembly 11 is of the double-break type since two interrupting gaps areprovided between the two movable tubular contact members 33, 33a andtheir associated stationary contact members 31, 31a.

The moving contact assembly is supported by a metal casting support 36mounted upon a support member 37, which, in turn, is mounted upon theupper end of the insulating supporting column 15 and provides an exhaustpassageway 37. The rotatable contact arms 34 and 34a are mounted uponpivot pins 38 and 38a, respectively, which are mounted in the metalsupport casting 36. The arms 34 and 34a are connected by links 39 and39a respectively, to a rotatable crank-arm 41 on an operating driveshaft 42. The drive shaft 42 extends to the outside of the pressurizedtank 14 through a suitable shaft seal (not shown), and may be driven byany suitable operating mechanism of a type well known in the art. Thecasting 36 may be made in. two halves, one of which is shown in thedrawing.

As shown in FIG. 4, the drive shaft 42 extends through the outer sidewall of the pressurized metallic tank 14 and is actuated in the openingand closing directions by a hydraulic mechanism 70, comprising ahydraulic cylinder 71, within which moves a hydraulic piston member 72.The hydraulic piston member 72 is connected to a piston rod 73 pivotallyconnected, as at 74, to a crank-arm 75 affixed to the external end ofthe operating drive shaft 42.

A hydraulic line 78 interconnects the upper end of the hydrauliccylinder 71 with an operating master valve, generally designated by thereference numeral 79, disposed within the mechanism compartment 20 atground potential, and which is electrically actuated by a doublesolenoiddevice 80 also at ground potential. As shown in FIG. 4, thedouble-solenoid device 80 comprises a pair of armatures 81, 82,associated with energizing windings 83, 84, which may be energized bythe closing of an open push-button 90, or the closing of a close pushbutton 91, as shown in FIG. 4.

Operation of the hydraulic master valve 79 at ground potential withinmechanism compartment 20 will interconnect the high-pressurev hydraulicfluid from an accumulator 85 through the master hydraulic valve 79, andinto the particular end of the hydraulic cylinder 71 depending on whichparticular operating button 90, 91, is pressed. Also, as well known bythose skilled in the art, a sump 94 may be provided to be connected tothe end of the hydraulic operating cylinder 71 in which the pressure isto be reduced.

FIG. 4 shows the electrical operating conditions at the end of theclosing operation of the circuit interrupter 10. It will be noted thatthe closing button 91 has energized the solenoid 84 to effect rotationof the master valve 79 to the position indicated, whereby theaccumulator is connected to the lower end of the hydraulic cylinder 71,thereby forcing the hydraulic piston 72 upwardly, and effecting aclosing operation of the driving crank 75. This will close the movablecontacts 33, 33a as shown in FIG. 2.

The downstream blast valve 26 is essentially of the balanced type, andis held closed against the valve seat 27 by the compression spring 28.The blast valve 26 has a skirt 43 surrounding an upwardly extendingportion 44 on the support member 37. An exhaust opening 45 in thesupport 37 provides an exhaust passageway from the interior of the tank14 into the upstanding insulating column 15 when the blast valve 26 islowered to open the valve opening 25. The blast valve 26 has a stem 46,which extends upwardlly through a valve guide 47 in the metal casting36. The upper end of the valve stem 46 has a plurality of ratchet teeth48 provided thereon. The teeth 48 are engaged by a spring-biased pawl 49carried by a bifurcated rod 51 pivotally attached to the crank-arm 41 bya pin 52, which also attaches the links 39 and 39a to the crank arm 41.Thus, the blast valve 26 is opened simultaneonsly with the contactmembers 33, 33a of the interrupter 11, as will be described more fullyhereinafter.

The contact member 35, which bridges hub portions of the contact arms 34and 34a is disposed within a recess in the metal casting 36, and isbiased into engagement with the hub portions by compression springs 53.As previously explained, the bridging member 35 electrically connectsthe moving contact members 33 and 33a in series-circuit relation.

The hollow contact members 33 and 33a are arcuate in shape since eachmoves in an arc defined by the rotatable contact arm 34 or 34a along theexhaust passageway 37'. The metal casting member 36 has arcuatepassageways 54 and 54a therein for receiving the moving contact members33 and 330, respectively. The passageways 54 and 54a communicate withthe blast valve opening 25, which, in turn, communicates with the in-'terior of the supporting column 15 through the opening 45 in the supportmember 37.

An opening operation is as follows: Upon receipt of the proper signal,the operating shaft 42 is rotated clock- Wise by the operatingmechanism, thereby moving the crank-arm 41 downwardly. This rotates thecontact arms 34 and 34a in opposite directions through the links 39 and39a, respectively, thereby disengaging the contact members 33 and 33afrom the stationary contact fingers 31 and 31a, respectively. Arcs areestablished, which quickly transfer to are horns 55 and 55a,respectively, as indicated by the arcs 56 in 'FIG. 3. At the same time,the downward motion of the crank-arm 41 drives the blast valve 26downwardly through the ratchet assembly 48, 49. This causeshigh-pressure sulfur-hexafiuoride (SP gas to flow from the interior ofthe tank 14 through the hollow contact members 33 and 33a, the exhaustpassageway 37', the valve opening 25, and the passageway 45 into thelow-pressure chamber inside the upstanding insulating column 15. Thus,the hollow moving contact members 33, 33a serve as orifices for the gasflow. This flow of gas effects arc interruption in a manner somewhatsimilar to that described in Patent No. 3,154,658, issued Oct. 27, 1964to G. Colclaser and R. N. Yeckley and assigned to the assignee of theinstant application.

As described in the aforesaid patent, there is provided an axial flow ofgas through the mouth of the orifice contacts 33, 33a, but also there isprovided a cross-blast action of the gas, since the arc is drawn betweenthe tip portion of the arcing horn and the inner side wall of themovable hollow contact, as shown by the arcs 56 in FIG.

3. As a result, there is provided both a cross-blast action and an axialflow blast action of the gas during an interruption operation.

Downward motion of the blast valve 26 is stopped by a projection 57engaging a butter assembly 58 in the portion 44 of the supporting member37. Just prior to reaching the full-open position, the pawl 49 isdisengaged from the ratchet teeth 48 by a pin 59, thereby permitting theblast valve 26 to be reclosed by its biasing spring 28. In this manner,the quantity of the high-pressure interrupting gas used during aninterruption is' conserved. As previously explained, gas is drawn fromthe lowpressure chamber inside the column and returned by the compressor19 through the insulating tube 29 to the high-pressure chamber insidethe metal tank 14.

From the foregoing description it is apparent that the inventionprovides a live-tank breaker, with contacts operated in a high-pressuregas, such as sulfur-hexafluoride (S1 gas, resulting in a structure ofminimum required contact separation. More efiicient use of the gas isobtained, when compared to prior breakers of the dualpressure type, witha possible resultant of lower maximum gas pressures, and a correspondingreduction in auxiliary heater requirements. The double-break interrupterunit 11 is suitable for use at relatively high voltages, and, aspreviously explained, two or more interrupting assemblies 11, 12 may beconnected in seriescircuit relation, thereby further increasing theservice voltage. Minimum mass is accelerated, resulting in reducedmechanism requirements. The downstream blast valve arrangement makeshigh-pressure gas available right at the contacts, and two-cycleoperation is easier to obtain than with upstream valve arrangements.

Reduced tank size is feasible because of the excellent dielectricproperty of the high-pressure sulfur-hexafluoride (SP gas or otherinterrupting gas. Maintenance is simplified since only the high-pressuregas need be removed to gain access to the interior of the tank 14, theblast valve 26 effectively sealing the low-pressure side. The operatingmechanism 70 can be serviced without disturbing the gas since it ismounted exteriorly of the pressurized tank 14.

Since numerous changes may be made in the abovedescribed construction,and different embodiments of the invention may be made without departingfrom the spirit and scope thereof, it is intended that all subjectmatter contained in the foregoing description, or shown in theaccompanying drawing, shall be interpreted as illustraive and not in alimiting sense.

We claim as our invention:

1. A double-break circuit interrupter comprising a spherical tankcontaining an interrupting gas at a relatively high pressure, a columnsupporting and insulating the spherical tank from ground, a singlespring-biased blast valve normally closing an opening between the tankand the column, two spaced relatively stationary contact membersdisposed inside the tank adjacent opposite ends thereof, twoseries-connected hollow rotatably movable contact members engaging thestationary contact members, a pair of rotatable crank-arms (34) carryingthe movable contact members, operating means for disengaging the contactmembers in a rotatable fashion and opening the single blast valve tocause gas to flow from the spherical tank through the hollow contactmembers and through the single valve opening into the supporting columnto interrupt the arcs drawn between the separated contact members, andthe axis of rotation (38) for the rotatable crank-arm (34) being inclose proximity to the center of the spherical tank.

2. A double-break circuit interrupter comprising a tank containing aninterrupting gas at a relatively high pressure, a column supporting andinsulating the tank from ground, a spring-biased blast valve normallyclosing an opening between the tank and the column, two spacedrelatively stationary contact members disposed inside the tank, twoseries-connected hollow rotatable contact members engaging thestationary contact members, and operating means for driving therotatable members toward each other to disengage them from thestationary contact members and for opening the blast valve to cause gasto flow from the tank through the hollow contact members and the valveopening into the supporting column to interrupt the arcs drawn betweenthe separated contact members.

3. A double-break circuit interrupter comprising a metal tank containingan interrupting gas at a relatively high pressure, a column supportingand insulating the metal tank from ground, a spring-biased blast valvenormally closing an opening between the metal tank and the column, twospaced relatively stationary contact members disposed inside the tank,two series-connected hollow rotatable contact members engaging thestationary contact members, operating means for driving the rotatablemembers toward each other to disengage them from the stationary contactmembers and to open the blast valve to cause gas to flow from themetallic tank through the hollow contact members and the valve openinginto the supporting column to interrupt the arcs drawn between theseparated contact members, and means permitting the blast valve to bereclosed by its biasing spring at the end of the opening operation.

4. A double-break circuit interrupter comprising a metal tank containingan interrupting gas at a relatively high pressure, a column supportingand insulating the tank from ground, a spring-biased blast valvenormally closing an opening between the tank and the column, two spacedrelatively stationary contact members disposed inside the tank, twoseries-connected hollow rotatable contact members engaging thestationary contact members, operating means for driving the rotatablemembers toward each other to disengage them from the stationary contactmembers, ratchet means actuated by the operating means to open the blastvalve to cause gas to flow from the tank through the hollow contactmembers and the valve opening into the supporting column to interruptthe arcs drawn between the separated contact members, and means forreleasing the ratchet means to permit the valve to be reclosed by itsbiasing spring at the end of the opening operation.

5. In a double-break circuit interrupter, in combination, a sphericalmetallic tank containing an interrupting gas at a relatively highpressure, a hollow column for supporting and insulating the tank fromground, two relatively stationary contact members mounted inside thetank in spaced relation, a supporting member disposed between saidcontact members and having an exhaust passageway therethrough with asingle valve open-ing communicating with the interior of the column, asingle spring-biasing downstream blast valve normally closing saidsingle valve opening, a hollow rotatably movable contact member engagingeach stationary contact member, a pair of rotatable crank-arms (34)carrying the movable contact members, operating means for moving thehollow contact members into said exhaust passageway to disengage themfrom the stationary contact members and for opening the singledownstream blast valve to cause gas to flow from the tank through thehollow contact members and the single valve opening into the supportingcolumn, and the axis of rotation (38) for the rotatable crank-arms (34)being in close proximity to the center of the spherical tank.

6. In a double-break circuit interrupter, in combination, a metallicspherical tank containing an interrupting gas at a relatively highpressure, a hollow column for supporting and insulating the tank fromground, two relatively stationary contact members mounted inside thetank in spaced relation adjacent opposite ends thereof, acentrally-located supporting member disposed between said contactmembers and having an exhaust passageway therethrough with a singlevalve opening communicating with the interior of the column, a singlespring-biased downstream blast valve normally closing said single valveopening, a hollow contact member engaging each stationary contactmember, a contact arm rotatably mounted on the centrally-locatedsupporting member for carrying each hollow contact member, and operatingmeans for driving the contact arms in opposite directions to disengagethe hollow contact members from the stationary contact members and movethem into said passageway, said operating means also opening said singleblast valve to cause gas to flow from the tank through the hollowcontact members and the single valve opening into the supporting column,and the axis of rotation (38) for the rotatable contact arms (34) beingin close proximity to the center of the spherical tank.

7. In a double-break circuit interrupter, in combination, a metallictank containing an interrupting gas at a relatively high pressure, ahollow column for supporting and insulating the tank from ground, tworelatively sta tionary contact members mounted inside the tank in spacedrelation, a supporting member disposed between said contact members andhaving an exhaust passageway therethrough with a single valve openingcommunicating with the interior of the column, a single spring-biasedblast valve normally closing said single valve opening,- a hollowrotatable contact member engaging each stationary contact member, acontact arm rotatably mounted on the supporting member for carrying eachhollow rotatable contact member, a bridging contact member engaging therotatable contact arms to electrically conmeet the hollow contactmembers in series-circuit relation, operating means for driving therotatable contact arms in opposite directions to disengage the hollowcontact members from the stationary contact members and move them intosaid exhaust passageway, and ratchet means driven by the operating meansto open the single downstream blast valve to cause gas to flow from thetank through the hollow contact members and the valve opening into thesupporting column.

8. In a double-break circuit interrupter, in combination, a metallictank contain-ing an interrupting gas at a relatively high pressure, ahollow column for supporting and insulating the tank from ground, tworelatively stationary contact members mounted inside the tank in spacedrelation, a centrally-located supporting member disposed between saidcontact members and having an exhaust passageway therethrough with asingle valve opening communicating with the'interior of the column, asingle spring-biased downstream blast'valve normally closing said singlevalve opening, a hollow rotatable contact member engaging eachstationary contact member, a contact arm rotatably mounted on thesupporting member for carrying each hollow rotatable contact member, abridging contact member engaging the contact arms to electricallyconnect the hollow rotatable contact members in series-circuit relation,operating means for driving the contact arms in opposite directions todisengage thehollow rotatable contact members from the stationarycontact members and move them into said exhaust passage- Way, ratchetmeans driven by the operating means to I exhaust passageway, meansdefining a pair of arc-extinguishing units disposed within saidspherical tank means and comprising each a relatively stationary contactcarried by the interior end of one of said terminal bushings and acooperable rotatably movable tubular contact movable along said exhaustpassageway, a rotatably movable crank-arm (34) for moving each movablecontact, means defining a single centrally-located downstream blastvalve communicating with said exhaust passageway and exhausting into thesupporting insulating column,

- means including a rotatable drive-shaft (42) extending through thewall of said tank means for effecting separation of the pair of movabletubular contacts and opening of said single downstream blast valve,means for effecting rotation of said drive-shaft externally of said tankmeans, whereby an exhausting flow of highpressure gas will flow out ofsaid spherical tank means through the pair of movable tubular contactsand past the single opened blast valve into the insulating supportingcolumns for arcextinguishing purposes, and the axis of rotation (38) forthe rotatable contact arms (34) being in close proximity to the centerof the spherical tank.

10. The combination according to claim 9, wherein a releasable ratchetmeans interconnect opening driving motion of said drive shaft andopening motion of a blastvalve stem.

11. The combination of claim 9, wherein hydraulic means at highpotential disposed externally of the metallic tank means and operated atground potential causes rotation during the opening and closingoperation of the rotatable drive-shaft (42).

References Cited UNITED STATES PATENTS 2,454,586 11/1948 Amer. 3,275,7789/1966 Morioka. 3,284,602 11/ 1966 Friedrich et al.

3,327,082 6/1967 Van Sickle et a1. 3,356,809 12/1967 Colclaser et a1.

FOREIGN PATENTS 1,1174,400 7/ 1964 Germany.

ROBERT S. MACON, Primary Examiner.

